The Parallel ATA (Advanced Technology Attachment) specification has defined the standard storage interface for PCs since the early 1980s. Parallel ATA provides low cost, broad operating system support, and steady evolution. Over time, parallel ATA has continuously evolved to support higher speed and performance. However, due to several reasons, including performance headroom, cabling issues, and voltage tolerance requirements, a new storage interface known as Serial ATA has recently been created.
Serial ATA may combine software transparency, low cost, scalability, and design flexibility to overcome the limitations of parallel ATA. Point-to-point data rates of 1.5 Gbps may be attainable with Serial ATA. Although SATA provides many benefits over PATA, there remains a large installed user-base of PATA compatible storage devices and computers. To continue to use the existing PATA compatible storage devices, bridge devices have been developed to interface PATA devices to SATA compatible computer systems.
FIG. 1 shows a conventional computer system 10 that communicates information via a SATA link 11. The computer system 10 includes a device bridge 12 to interface a PATA storage device 14 to a host controller 16 through a host bridge 18. The device bridge 12 and the host bridge 18 may each convert PATA formatted information to SATA formatted information and SATA formatted information to PATA formatted information. The device bridge 12 and the host bridge are generally not interchangeable due to differences in the header information that each of the bridges 12 and 18 generate when converting information between the SATA to PATA formats.